self.addEventListener('activate', function (event) {
    console.log('activate:' + ' ' + angular.toJson(event));
});

self.addEventListener('fetch', function (event) {
    console.log('fetch:' + ' ' + angular.toJson(event));
});

self.addEventListener('push', function (event) {
    console.log('push:' + ' ' + angular.toJson(event));
});